Characteristics of Calibration Curves for Ni-Zn Binary Alloys in Low-Pressure Argon Laser-Induced Atomic Emission Spectrometry

A calibrational relation between the emission intensity ratio and the atomic ratio was investigated in a Ni-Zn binary alloy system when a low-pressure argon laser-induced plasma was employed as the excitation source. The sampling amount of the alloy samples was drastically reduced compared to a pure Zn sample, indicating that Zn atoms became less evaporated due to alloying with Ni. The Ni-Zn binary alloy has several metallurgical phases depending on the chemical composition : alpha-phase (Ni solid solution with Zn), beta-phase (NiZn intermetallic compound), and gamma-phase (NiZn(3) intermetallic compound), which could each suppress the evaporation of Zn atoms. Calibration curves for several pairs of Ni and Zn emission lines did not follow a linear relationship, even when several measuring conditions such as the gate width and the delay time were varied. The reason for this would be that the evaporation behavior of Zn is different among the alloy phases and their metallurgical structures in the Ni-Zn alloy system.